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[Bernard Amadon <bernard.amadon@cea.fr>]

Dear Ganesh,

I agree with you, it is not so obvious in particular because the 
projected dos
is a sum of the square modulus of the projection of  kohn sham 
wavefunctions on atomic orbitals.
So  the dos in real spherical harmonics basis cannot be simply deduced 
from the dos in the complex harmonics basis.
So you have to compute it by yourself or to modify the code.

Best regards
Bernard



Ganesh Panchapakesan a écrit :
> Dear Bernard,
>
> Thank you for the reply.  Indeed, I see that using imag. Ylm's, 
> DOS(L,M)==DOS(L,-M).
>
> It is also clear that if I knew the projected 'dos' in terms of the 
> real. sph. harms., then DOS(L,M)=(dos(L,M)+dos(L,-M))/2.0 , where 
> 'dos' is for projections on real sph. harms.  But going the other way 
> around, from DOS to dos, doesn't seem to be possible due to the 
> identity in the first line.  It seems I have to explicitly compute 
> 'dos' .  Maybe there is a relation between dos(L,M) and dos(L,-M) that 
> I am missing, but I don't see it in my derivation.
>
> Thanks.
>
> Ganesh
>
>
>
> On Wed, Jan 13, 2010 at 9:11 AM, Bernard Amadon <bernard.amadon@cea.fr 
> <mailto:bernard.amadon@cea.fr>> wrote:
>
>     Dear Ganesh
>
>     Prtdosm computes M-resolved partial dos in the complex spherical
>     harmonics, it explains why you have
>     DOS(L,M) == DOS(L,-M) (without spin-orbit). In the contrary, LDA+U
>     occupation matrix is in the real spherical harmonics basis.
>     You could use prtfatbands which computes band structure in the
>     real spherical harmonics basis, but
>     to have the partial dos, you can use the conversion from complex
>     to real spherical harmonics,
>     apply it to the dos, and you will have the partial dos in the real
>     spherical harmonics which is more
>     convenient for the interpretation.
>
>     Best regards
>     Bernard
>
>
>
>
>
>     Ganesh Panchapakesan a écrit :
>
>         Dear All,
>
>         I am trying to compute the partial DOS (projected on to
>         (atom,L,M) ) of an anti-ferro. system using PAW - GGA with
>         v5.7.4.  The system is metallic.  I use the following options:
>         prtdos 3, prtdosm 1, ngkpt 10 10 10, shiftk 0 0 0, natsph 1,
>         iatsph 1, ratsph 2.31, iscf -3 to compute the DOS using the
>         tetrahedron method and project onto the (L,M) centered on atom
>         'i' (ratsph =  r_c of PAW dataset)
>
>         Although the partials obey the condition: Sum(m)DOS(L,M) ==
>         DOS(L), the result of the partials always follows this
>         identity: DOS(L,M) == DOS(L,-M), even when I expect the
>         different d-orbitals (i.e. L=2) to have a different
>         occupations (I see that from the occupation matrices in a +U
>         calculation). As a result, the integral of the  DOS(L,M) up to
>         the Fermi level does not correspond to the occupation number
>         from the +U calculation.  I have tried with both the pure GGA
>         density and GGA+U density as inputs to the DOS calculation.
>
>         Any suggestions/clarifications will be very much appreciated.
>         If anyone knows that this is a problem but it is fixed in
>         v5.8.4 that would also help.
>         Thanks.
>
>         Ganesh  
>
>
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